The vast studies in the careful control of quantum states, motivated by the quantum information science with an aim to develop quantum information processors, have also enabled measurements in unprecedented precision and accuracies. The precision measurements using these quantum technologies can be adopted to answer some of the fundamental questions of quantum mechanics, and possibly expand the quantum mechanical description to a macroscopic system, "the classical big system!". One of the promising systems for the understanding of the macroscopic quantum system is the optomechanical system. Recently, the near ground-state cooling of these systems have been reported and rapid development in the quantum control of the optomehcanical system as well as the control with other quantum systems via hybridization are taking place. While a large variety of optomechanical systems in mass, frequency and dimensional size are developed, the implication of these variation for the understanding of the macroscopic quantum system is still unclear. The aim of this workshop is to review the current technologies on the optomechanical systems and to discuss possible new scientific interests for a macroscopic quantum mechanical system. For the selected young researcher, we prepare the financial support.